Welcome to a world in which where humans and demons coexist. Souls harboring strong emotions and deep regrets at their time of death are transformed into Archdemons. The Archdemons have the power to corrupt logic and reason in the world and contaminate the surrounding environment. Creatures tainted by this demonic power turn into lowly monsters which operate solely on raw instinct.Faced with the threat to the world posed by five extremely powerful Demon Girls, the Oracle is forced to dispatch Homura Hime - the "Flame Princess" and ultimate demon killer, and Ann, a messenger who has been entrusted with the divine mission of "purifying the world and bringing an end to all evil".